A communication status in a radio network changes depending on a distance from a base station, surrounding environment and time and the like. Therefore, it is necessary that a manager or an operator of a network always ascertains quality status of various areas or cells in the radio network in order to improve quality.
A direct method for measuring the quality status of various areas is that an operator goes to the various areas and performs wave measurement. This method is called Drive Test. However, in the case where the drive test is used for periodically investigating all areas, finding areas that need to be improved, and addressing the improvement, it is feared that the cost becomes very high.
From this viewpoint, a technique is currently being discussed in which a user apparatus in an area, instead of the operator, measures a radio quality and reports a measurement result to the operator. This technique is called MDT (Minimization of Drive Test). For example, the non-patent document 1 describes the MDT.